@bosejs/runtime

The tiny browser loader for Bosejs — resumes event handlers without hydration.

What it does

The runtime is the "heart" of Bosejs. It's a small (<2KB) script that runs in the browser and:

1. Intercepts events via a single delegated listener on document
2. Reads bose:on:* attributes to find which chunk handles the event
3. Fetches the chunk lazily on first interaction (subsequent clicks use the cached module)
4. Deserializes bose:state and injects it into the chunk as __BOSE_STATE__
5. Executes the handler — the island "resumes" from exactly where the server left off
6. Syncs signals — updates any DOM node with a matching bose:bind attribute

Install

This package is installed automatically when you install @bosejs/core. You don't need to install it directly.

npm install @bosejs/core   # pulls in @bosejs/runtime automatically

How resumption works

Your HTML looks like this after SSR:

<span bose:bind="count">0</span>
<button
  bose:on:click="chunk_a1b2c3.js"
  bose:state='{"count":0}'>
  +
</button>

On first click, the runtime:

• Fetches chunk_a1b2c3.js (one network request, then cached)
• Injects { count: signal(0) } as __BOSE_STATE__
• Runs the chunk (count.value++)
• Finds <span bose:bind="count"> and updates it to 1

No framework boot. No virtual DOM. No re-render.

License

MIT © Bosejs Contributors